Plating of Cu and Ni metals on Mg-ferrite sintered bodies by an electroless method and an investigation of magnetic behavior

Abstract

MgFe2O4 nanoparticles were synthesized using sol–gel autocombustion method. The structural and phase formation of the samples were studied through X-ray diffraction patterns. The results indicated that the MgFe2O4 phase was formed along with a second phase of Fe2O3 in the calcinated temperatures up to 900 °C. The desired single phase was produced by elevating calcination temperature to 1000 °C for 2 h. This is further confirmed by Fourier transform infrared spectroscopy, showing two absorption bands corresponding to the vibration of tetrahedral and octahedral complexes at ~ 570 and ~ 430 cm−1, respectively. The microstructure and morphology of the samples were studied using scanning electron microscopy; exhibiting even and rectangular-shaped particles with the average size of 270 nm. In the second stage, the 1000 °C—calcinated powders were pressed under 500 MPa and subjected to sintering from 1350 to 1500 °C with 50 °C increments for 1 h. The bulk density of the sintered bodies increased from 3.9 (at 1350 °C) to 4.25 g/cm3 (at 1500 °C) and the theoretical porosity reduced from 18.85 to 7%, respectively. Studying their magnetic properties, through a permagraph loop tracer, revealed that the saturation magnetization (Ms) increased from 1200 to 1420 G and the intrinsic coercivity (HcJ) declined from 50 to 12 Oe, respectively. By plating of Cu and Ni metals on the 1500 °C—sintered body samples revealed that the Ms value, however, remained constant, the HcJ reduced from 12 to 8 Oe, as compared to the 1500 °C—sintered body sample, which enable them promising candidates as inductor and transformer materials for high frequency applications.